Online research in philosophy

“Moorean Dogmatist” responses to external world skepticism endorse courses of reasoning that many people find objectionable. This paper seeks to locate this dissatisfaction in considerations about epistemic responsibility. I sketch a theory of immediate warrant and show how it can be combined with plausible “inferential internalist” demands arising from considerations of epistemic responsibility. The resulting view endorses immediate perceptual warrant but forbids the sort of reasoning that “Moorean Dogmatism” would allow. A surprising result is that Dogmatism’s commitment to immediate epistemic warrant isn’t enough to avoid certain standard arguments for skepticism about the external world.

‘Skepticism’ refers primarily to two positions. Knowledge skepticism says there is no such thing as knowledge, and justification skepticism denies the existence of justified belief. How closely the two views are related depends on the relationship between knowledge and justification: if knowledge entails justified belief, as many theorists say, then justification skepticism entails knowledge skepticism (but not vice versa). Either form of skepticism can be limited in scope. Global (or radical) skepticism challenges the epistemic credentials of all beliefs, saying that no one knows anything, or no belief is justified. More local skepticism is restricted to some domain; thus some skeptics question the epistemic credentials of beliefs about other minds (but not beliefs about one’s own mind), or beliefs concerning empirical matters (but not concerning a priori matters).

Two compelling and persistent projects of contemporary epistemology are engaging skepticism and searching for adequate epistemic principles. The former, of course, can be traced in various forms through the ancients and moderns, and the last decade has seen skepticism debated with renewed vigor. The centrality of skepticism in epistemology is manifest. It both presents a foil against which positive epistemic theses may be modified and tested, and offers powerful arguments that perhaps even lead to the conclusion that skepticism correctly captures our ultimate epistemic condition (Stroud, 1984).

“Moorean Dogmatist” responses to external world skepticism endorse courses of reasoning that many people find objectionable. This paper seeks to locate this dissatisfaction in considerations about epistemic responsibility. I sketch a theory of immediate warrant and show how it can be combined with plausible “inferential internalist” demands arising from considerations of epistemic responsibility. The resulting view endorses immediate perceptual warrant but forbids the sort of reasoning that “Moorean Dogmatism” would allow. A surprising result is that Dogmatism’s commitment to immediate epistemic warrant isn’t enough to avoid certain standard arguments for skepticism about the external world.

The projection lattices T(Mr), T(M2) of two von Neumann subalgebras Mr, M2 of the von Neumann algebra M are defined to be logically independent if A A B g 0 for any 0 g A E P(&r), 0 g B E 7 (M2). After motivating this notion of independence it is shown that 7 (Mr), 7 (M2) are logically independent if Mr is a subfactor in a finite factor M and T(&r),V'(M2) commute. Also, logical independence is related to the statistical independence conditions called C*-independence W*- independence and strict locality. Logical independence of T(Mr), T(M2) turns out to be equivalent to the C*- independence of (Mr, M2) for mutually commuting Mr, M2, and it is shown that if (Mr, M2) is a pair of (not necessarily commuting) von Neumann subalgebras, then T(&r),V'(M2) are logically independent if (Mr, M2) is a W*-independent pair or if Mr, M2 have the property of strict locality.

The skepticism I propose to discuss concerns the reality of an external world of perceivable material objects. There are three questions our skeptic may ask. The first is nonmodal and nonepistemic: Are some of the objects we perceive real? The second is also nonmodal but epistemic: Do we know, or at least have evidence, that some of the objects we perceive are real? The third is both modal and epistemic: Can we know, or at least have evidence, that some of the objects we perceive are real? By definition, the epistemic questions are the ones the skeptic asks. But I shall take the first, the nonepistemic question as primary; it is, surely, also the one in which we, including the skeptic, are really interested. The traditional approach to skepticism has been to take it as asking one or both of the epistemic questions. I suggest that..

Skepticism and its Legacy (first 1 1/2 weeks) i) Skepticism about the external world: Skepticism in some form or another is a philosophical perennial, but even so it is not unreasonable to suggest that with Descartes, skepticism of an entirely new form made its first appearance on stage. Descartes deployed a radical doubt about the external world, with methodical ambitions, and in doing so he might be taken to have raised the stakes for epistemology. What if the Cartesian response to Skepticism fails? Is our ordinary knowledge of the world impeached if we cannot refute the hypothesis that we are dreaming, or that we are the playthings of a malign demon? There is also a historical question: is Cartesian skepticism interestingly different from the Pyrrhonian and academic skepticism that was "in play" long before Descartes?

In ' Unnatural Doubts' Michael Williams argues that Cartesian skepticism is not truly an "intuitive problem" (that is, one which we can state with little or no appeal to contentious theories) at all. According to Williams, the skeptic has rich theoretical commitments all his own, prominent among which is the epistemic priority thesis. I argue, however, that Williams's diagnostic critique of the epistemic priority thesis fails on his own conception of what is required for success. Furthermore, in a brief "Afterword" I argue that the later Wittgenstein (to whom Williams sometimes appeals) would concur with my critique of Williams's antiskeptical efforts.

For a putative knower S and a proposition P , two types of skepticism can be distinguished, depending on the conclusions they draw: outer skepticism , which concludes that S does not know that P , and inner skepticism , which concludes that S does not know whether P . This paper begins by showing that outer skepticism has undesirable consequences because that S does not know that P presupposes P , and inner skepticism does not have this undesirable consequence since that S does not know whether P does not presuppose P . We indicate that the two types of skepticism aim to different loci of doubts: while outer skepticism doubts whether we can gain an epistemic warrant for the actuality, inner skepticism doubts whether we can gain epistemic identification of the actuality. It is further indicated that responses to skepticism from externalist theories, as well as from fallibilist internalist theories, can only respond to outer skepticism but not to inner skepticism.

I defend the view that there is a privileged class of propositions – that there is an external world, among other such 'hinge propositions'– that possess a special epistemic status: justified belief in these propositions is not defeated unless one has sufficient reason to believe their negation. Two arguments are given for this conclusion. Finally, three proposals are offered as morals of the preceding story: first, our justification for hinge propositions must be understood as defeatable, second, antiskeptics must explain our knowledge in the face of 'actual world' skepticism (like dreaming skepticism) as much as in the face of the usual sort (like brain-in-vat skepticism), and, finally, our justification for hinge propositions is basic (i.e. non-inferential).